JPH06104551A - Production of printed wiring board and method for ptinting wiring on glass plate - Google Patents

Abstract

PURPOSE:To produce a printed wiring board through reduced number of production steps while causing no damage on the environment and to print a conductor pattern firmly and stably onto a glass plate having relatively large size. CONSTITUTION:A metal plate 10 preferable as a conductor pattern material is prepared and a glass substrate 12 is superposed thereon. It is then irradiated with YAG laser beam from above the glass substrate 12. The YAG laser beam transmits through the glass substrate 12 and impinges on the metal plate 10. Metal is thermally melted locally at a part of the metal plate 10 irradiated with laser beam and eventually evaporates therefrom. Since the metal plate 10 and the glass substrate 12 are substantially enclosed, evaporated metal is not scattered but adheres onto the surface of an opposing glass substrate 12. When the point or region to be irradiated with YAG laser is controlled to form a pattern, a conductor pattern 15 is formed on the glass substrate 10 and secured thereto.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for printing wiring on a transparent or semitransparent insulating plate such as glass and a method for manufacturing a printed wiring board.

[0002]

2. Description of the Related Art A printed wiring board is one in which a conductor pattern based on electrical design is formed and fixed on the surface (or surface and inside) of an insulating substrate and is generally used as a circuit board for various electric devices. It is used. As a conventional printed wiring board manufacturing method, an etching method and a plating method are well known. The etching method requires coating the entire surface of an insulating substrate (copper-clad laminate) with a copper foil, exposing and developing the conductor pattern, and then dissolving and removing the metal foil other than the conductor pattern with a chemical. To make a printed wiring board of
It is the mainstream today. In the plating method, a resist is applied to the part of the insulating substrate where the copper foil is not attached, excluding the conductor pattern, and copper plating is applied only to the conductor pattern part in the electroless copper plating process to make the required printed wiring board. Is the way. As the insulating substrate, a paper-based phenol resin laminated plate, a glass cloth-based epoxy resin laminated plate, etc. are often used.

Further, conventionally, conductor patterns such as antennas and heater wires have been formed on the surface of a glass plate used for windows of automobiles, doors for bilging, and the like.
Since such a glass plate has a size significantly larger than that of a printed circuit board and has a low wiring density, the above-mentioned etching method or plating method is not used. For example, a conductor pattern is printed with metal powder and ink. The method of doing is done.

[0004]

As described above, in the conventional printed wiring board manufacturing method, many steps such as resist coating, exposure / development, etching or plating are used for printing a conductor pattern on an insulating substrate. Is needed. Further, since the insulating substrate is a laminated plate in the first place, many steps are required for its manufacture. In the case of a copper-clad laminated plate, the number of steps is further increased by sticking a copper foil on the surface. Further, since the conventional manufacturing method uses a harmful substance such as a chemical, care must be taken in its management and handling, and disposal of the product is troublesome.

Further, in the conventional method of forming a conductor pattern on the surface of a glass plate as described above, the conductor pattern is easily peeled off from the glass plate due to moisture, dirt, rubbing, etc., and the conductor pattern must be covered with a protective film. It has the drawback that it must be done.

The present invention is intended to solve the above-mentioned problems, and an object thereof is to provide a method for producing a printed wiring board which has a small number of steps and is environmentally safe. An object is to provide a method capable of stably printing a pattern.

[0007]

In order to achieve the above object, a method for manufacturing a printed wiring board according to the present invention is such that one main surface of a transparent or semitransparent insulating substrate is a conductive metal foil or a metal plate surface. In accordance with the above, laser light is radiated through the insulating substrate to the surface of the metal foil or metal plate in a desired pattern, and the metal of the metal foil or metal plate irradiated with the laser light is heated to remove one of the insulating substrates. A method of forming and fixing a desired conductive pattern on the main surface was adopted.

The method of printing wiring on the glass plate of the present invention is such that one main surface of the transparent or translucent glass plate is aligned with the surface of the conductive metal foil or metal plate, and laser light is passed through the glass plate. Irradiate the surface of the metal foil or metal plate with a desired pattern, and heat the metal of the metal foil or metal plate irradiated with the laser light to form and fix a desired conductive pattern on one main surface of the glass plate. I decided to do it.

[0009]

FUNCTION YAG laser light, for example, has a wavelength of about 1.06 μm and passes through a transparent body or a semitransparent body. In the present invention, a laser beam having such a predetermined wavelength is passed through a transparent or semitransparent insulating substrate such as a glass substrate,
Irradiate a metal plate or foil that is a conductive material. Then, in the portion of the metal plate or the metal foil irradiated with the laser light, the metal is locally heated and melted or evaporated by the laser energy. The heating, melting, or evaporation of the metal occurs on the contact surface between the metal plate or metal foil and the transparent or semitransparent insulating substrate. Therefore, the sublimated metal does not scatter and adheres to the surface of the opposing insulator. By irradiating the metal plate or the metal foil with laser light in a desired pattern, the metal adhesion portion on the surface of the insulating substrate can be formed in a desired pattern. In this way, a desired conductor pattern can be formed on a transparent or semitransparent insulating substrate or glass plate.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings. A method of manufacturing a printed wiring board according to an embodiment will be described with reference to FIG. First, as shown in FIG. 1 (A), a metal plate 1 made of a metal desirable as a conductor pattern material for a printed wiring board, for example, copper, silver, aluminum or the like having high electric conductivity 1
Prepare 0. Next, as shown in FIG. 1B, a transparent or semitransparent insulating substrate such as a glass substrate 12 is superposed on the metal plate 10. At this time, the glass surface (principal surface) to which the conductor pattern is to be attached is faced down (opposed to the upper surface of the metal plate 10) to bring them into close contact with each other.

Next, as shown in FIG. 3A, YAG laser light LA is irradiated from above the glass substrate 12. YA
Since the G laser beam LA has a wavelength of about 1.06 μm, it passes through the glass substrate 12 and irradiates the metal plate 10. At the portion of the metal plate 10 irradiated with the laser beam LA, the metal is locally heated and melted or evaporated by the laser energy. Since the gap between the metal plate 10 and the glass substrate 12 is substantially sealed, the metal heated, melted or vaporized by the metal plate 10 does not scatter and adheres to the surface of the glass substrate 12 facing the metal plate 10. Therefore, when the glass substrate 12 is separated from the metal plate 10, the lower surface 1 of the glass substrate 12 as shown in FIG.
The metal-attached portion ME remains on 2A. In this way, the metal of the metal plate 10 is discretely adhered and fixed to the lower surface 12A of the glass substrate 12. By controlling the irradiation point or irradiation region of the YAG laser beam LA in a pattern, the conductor pattern 15 is formed and fixed on the glass substrate 12 as shown in FIG. 1 (C). The conductor pattern 15 is not easily peeled off even if it is rubbed, has durability against water and temperature change, and is stable over time.

FIG. 4 shows the structure of the laser emitting apparatus used in this embodiment. This laser emitting device irradiates the upper surface of the metal plate 10 with the YAG laser light LA through the glass plate 12 and scans the laser beam spot in the XY directions to draw a desired pattern based on the circuit design. The image data defining this pattern is, for example, CAD.
It is input to a computer by (Computer Aided Design), stored in a printed wiring database, read from the database when the printed wiring is created, and given to the laser emitting device.

In this laser emitting device, the laser light LA coming directly from the YAG laser oscillator or coming through the optical fiber first enters the X-axis rotating mirror 24 and is totally reflected there, and then the Y-axis. The light enters the rotating mirror 26, is totally reflected by the mirror 26, and is then condensed by a condenser lens 28 near the lower surface of the glass plate 12 or the upper surface of the metal plate 10. The position of the laser beam spot on the metal plate 10 is the angle of the X-axis rotating mirror 24 in the X direction,
In the Y direction, it depends on the angle of the Y-axis rotating mirror 26.

The X-axis rotary mirror 24 is adapted to be rotationally oscillated in the directions of arrows A and A'by the X-axis galvanometer scanner 30. On the other hand, the Y-axis rotating mirror 26
The X-axis galvanometer scanner 32 indicates an arrow B,
It is designed to rotate and vibrate in the B'direction. A scanning control signal from a control unit (not shown) is applied to both scanners 30 and 32 via electric cables 34 and 36.

Therefore, each time the pulsed laser light LA from the YAG laser oscillator (not shown) enters through the optical fiber 20 at a predetermined timing, both scanners 30 and 32 rotate in the X-axis in synchronization therewith. By swinging the mirror 24 and the Y-axis rotating mirror 26 at a predetermined angle, a laser beam spot is focused and irradiated onto a predetermined position on the upper surface of the metal plate 10, and the irradiated metal is heated and melted or evaporated to be a glass plate. Attach to 12. Such that the heat melting or evaporation of such metal draws the desired pattern,
Scan the laser beam spot. Then, as shown in FIG. 1C, a desired conductor pattern 15 is formed and fixed on the lower surface of the glass plate 12.

In addition, in FIG. 1C, the FDP is schematically shown.
The wiring 15 for mounting the (Flat Dual in Package) integrated circuit package (not shown) on the glass substrate 12 is shown, but this is only an example for illustration, and a more complicated arbitrary conductor is shown. It is possible to form a pattern. Also, by adjusting the laser beam spot diameter,
It is possible to select an arbitrary wiring width for practical use.

Instead of the metal plate 10 as described above, it is possible to use a metal foil 14 as shown in FIG. 2A, for example. The metal foil 14 may be a metal foil desired as a material for the conductor pattern, for example, a copper foil, a silver foil, or an aluminum foil. In this case, as shown in FIG. 2B, the metal foil 14 may be laid on a suitable supporting plate 16 and the glass plate 10 may be superposed thereon. Then, for example, by the laser emitting device shown in FIG. 4, the YAG laser beam LA is irradiated onto the upper surface of the metal foil 14 through the glass plate 12, and a desired pattern is drawn while running the laser beam spot in the XY directions. As shown in (C), a desired conductor pattern 15 is formed and fixed on the lower surface of the glass plate 12.

As described above, according to the present invention, the metal plate 10 or the metal foil 14 serving as a conductive material is superposed on the glass substrate 10, and the laser light LA is passed through the glass substrate 10 to pass through the metal plate 1.
0 or the metal foil 14 is irradiated with the laser light L so that the irradiation pattern of the laser light LA matches the desired conductor pattern.
A desired conductor pattern can be printed on the surface of the glass substrate 10 only by scanning A. In this way, the printed wiring board can be manufactured by one step of substantially scanning with laser light. In addition, since chemicals such as resist and etching solution and organic solvents are not used, it is environmentally safe.

Although the scanning type laser device as shown in FIG. 4 is used in the above-mentioned embodiment, a mask type laser pattern forming device for projecting a pattern through a mask may be used. Also in the scanning method, instead of rotating the mirrors 24 and 26 to swing the laser light LA as in the device shown in FIG. 4, the entire emission unit or the glass substrate side is relatively moved to draw and form a pattern. You may do it. Further, not only one side of the glass substrate but also both sides can be printed with a conductor pattern to form a double-sided printed wiring board, and holes such as through holes may be formed. In addition, multilayer printed wiring boards and liquid crystal displays (LC
It is also possible to apply to D) and the like.

FIG. 5 shows an embodiment in which the present invention is applied to an antenna wire and a heater wire of a rear window of an automobile. In FIG. 5, the conductor pattern 42 printed on the upper inner surface of the rear window 40 is an antenna line for FM broadcast reception, and the conductor pattern 44 printed on the lower inner surface of the rear window 40 is for preventing fog. It is a heater wire. Since the rear window 40 is generally a glass plate having a curved surface, a metal foil may be used as the conductive material so as to follow the curved surface. As the material of the metal foil, a copper foil, an aluminum foil or the like having a high electric conductivity is suitable for the antenna wire 42, and a nichrome foil, a molybdenum foil or the like having a high resistance heating rate may be used for the heater wire 44. . As a method of drawing the patterns 42 and 44 on the rear window 40, the laser emitting unit is moved with the glass plate (rear window 40) side fixed, or the glass plate (with the laser emitting unit side fixed). Rear window 4
0) may be moved by an XY table or the like.

Further, the transparent insulator on which the wiring or the conductive pattern can be printed according to the present invention is not limited to glass, and transparent acrylic, plastic, ceramic or the like may be used. Furthermore, not only a transparent body but also a semitransparent body is possible.

[0022]

As described above, according to the method for manufacturing a printed wiring board of the present invention, a laser beam is irradiated through a transparent or semitransparent insulating substrate onto a metal plate or a metal foil matched with the laser beam, and laser energy is applied. By heating or melting or evaporating the metal of the metal plate or metal foil and attaching it to one main surface of the insulating substrate, it is possible to print a stable conductor pattern that is hard to peel off on the insulating substrate, and use chemicals etc. It is possible to manufacture the printed wiring board in substantially one step without using the above. Further, according to the method of printing wiring on the glass plate of the present invention, the metal plate or metal foil matched with it through the glass plate is irradiated with laser light, and the metal of the metal plate or metal foil is heated and melted by laser energy or By evaporating and adhering it to one main surface of the glass plate, it is possible to print a stable conductor pattern that is hard to peel off even on a glass plate having a relatively large size.

[Brief description of drawings]

FIG. 1 is a schematic perspective view for explaining a process of a method for manufacturing a printed wiring board according to an embodiment of the present invention.

FIG. 2 is a schematic perspective view for explaining a process of a method for manufacturing a printed wiring board according to another embodiment of the present invention.

FIG. 3 is a diagram for explaining the operation of the embodiment.

FIG. 4 is a perspective view showing a configuration of a laser emission device used in an example.

FIG. 5 is a schematic perspective view showing a rear window of an automobile in which an antenna wire and a heater wire are printed as a conductor pattern as an example to which the present invention is applicable.

[Explanation of symbols]

 10 Metal Plate 12 Glass Plate 14 Metal Foil 16 Support Plate 24 X-Axis Rotating Mirror 26 Y-Axis Rotating Mirror 28 Condensing Lens 40 Rear Window 42 Antenna Wire 44 Anti-fog Heater Wire

Claims (2)

[Claims] 1. A transparent or semitransparent insulating substrate having one main surface aligned with the surface of a conductive metal foil or metal plate, and laser light passing through the insulating substrate in a desired pattern on the surface of the metal foil or metal plate. A method for manufacturing a printed wiring board, which comprises irradiating and heating the metal of the metal foil or the metal plate irradiated with the laser beam to form and fix a desired conductive pattern on one main surface of the insulating substrate. 2. A transparent or translucent glass plate having one main surface aligned with a surface of a conductive metal foil or metal plate, and laser light passing through the glass plate in a desired pattern on the surface of the metal foil or metal plate. The wiring is printed on the glass plate characterized by irradiating and heating the metal of the metal foil or the metal plate irradiated with the laser light to form and fix a desired conductive pattern on one main surface of the glass plate. Method.